winform中DataGrid绑定combobox

private void AddBoxInDataGrid()
 2        {
 3            Company com = new Company();
 4            DataSet ds = new DataSet();
 5            ds = com.GetListAll();
 6            this.dgCompany.DataSource = ds.Tables["ds"];
 7            
 8            if(!this.dgCompany.TableStyles.Contains("ds")) 
 9            {
10                DataGridTableStyle dgdtblStyle = new DataGridTableStyle(); 
11　　　　        dgdtblStyle.MappingName = ds.Tables[0].TableName; 
12　　　　        this.dgCompany.TableStyles.Add(dgdtblStyle); 
13            }
14            DataGridTextBoxColumn dgtb = (DataGridTextBoxColumn)this.dgCompany.TableStyles[0].GridColumnStyles[8]; 
15            ComboBox cb = new ComboBox();
16            //combobox绑定数据库中CompanyType表
17            DataSet ds1 = new DataSet();
18            CompanyType ct = new CompanyType();
19            ds1 = ct.GetList();         
20            cb.ValueMember = "ID";
21            cb.DisplayMember  = "Name";
22            cb.DataSource = ds1.Tables[0].DefaultView;
23
24　　　        cb.Cursor = Cursors.Arrow; 
25　　　        cb.DropDownStyle= ComboBoxStyle.DropDownList; 
26　　　        cb.Dock = DockStyle.Fill; 
27            cb.SelectionChangeCommitted +=new EventHandler(cb_SelectionChangeCommitted);
28            dgtb.TextBox.Controls.Add(cb); 
29        }
30        private void cb_SelectionChangeCommitted(object sender, EventArgs e)
31        {
32            this.dgCompany[this.dgCompany.CurrentCell] = ((ComboBox)sender).Text;
33            index = ((ComboBox)sender).SelectedValue.ToString();
34        }